Can't tell ya about Texas, but here in AZ, it's being considered at this point a motorcycle. Ya gotta put all your stuff on the bike, lights, horn, etc. then take it down to MVD and hope they'll say it's safe enough for the street. But then you still gotta get a moto license.
Check with your local PD public information officers and see what they say. Sometimes the street officers don't have the latest rulings yet, so PIOs are prob. your best bet.
in mass anything under a 50 is considered a moped, and if you have a light, mirror, tail light and brake light you can register it leagally. i know a few people that have there 50's registered as a moped with out lights or anything. would like to find/ or make a light kit.